Steam-turbine.



No. 793,540. PATENTED JUNE 27, 1905. E. K. PURVIS.

STEAM TURBINE.

APPLICATION FILED FEB.13.1905.

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L9 AZ Z vewboc Ewe/[5 W A q Vi/imaoo a No. 793,540. PATENTED JUNE 27, 1905. B. K. PURVIS.

STEAM TURBINE.

APPLICATION FILED FBB.13,1905.

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v attozumg No. 793,540. PATENTED'JUNE 27, 1905. E. K. PURVIS.

STEAM TURBINE.

APPLIGATION FILED IEB.13,1905

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amen/boa Patented June 2'7, 1905.

ELMER K. PURVTS, OF MANCHESTER, IOWA.

STEAM-TURBINE.

SPECIFICATION forming part of Letters Patent No. 793,540, dated June 27, 1905.

Application filed February 13, 1905. gerial No. 245,451.

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Be it known that I, ELMER K. PURVIS, acitizen of the United States, residing at Manchester, in the county of Delaware and State of Iowa, have invented certain new and useful Improvements in Steam-Turbines; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in steam-turbines.

The object of the invention is to provide an engine of this character in which the full expansion of the steam will be utilized and a maximum amount of power obtained from the same.

Another object is to provide means whereby the turbine may be quickly reversed.

A further object is to provide means whereby the turbine may be changed from a highspeed to a low-speed high-power engine.

WVith these and other objects in view the invention consists of certain novel features of construction, combination, and arrangementof parts, as will be hereinafter described and claimed.

In the accompanying drawings, Figure 1 is a side elevation of a turbine constructed in accordance with the invention. Fig. 2 is a vertical longitudinal sectional View of the same. Fig. 3 is a vertical transverse sectional view through the first inlet or expansion chamber, showing the reversing mechanism, parts of the same being broken away to illustrate the arrangement of the steam-inlet ports. Fig. 4 is a similar view through the second inlet or expansion chamber. Fig. 5 is a similar view through the exhaust-chamber looking in the direction of the arrow and showing the exhaust-controlling mechanism, parts of the same being broken away to illustrate the arrangement of the exhaust-ports. Fig. 6 is a face view of one of the rotary pistens or turbine-wheels. Fig. 7 is a detail fragmentary sectional view through one of the port-hole plates and the turbine-wheel, showing the relative arrangement of the outer series of port-holes and the corresponding series oi blades of the turbine-wheel for running the engine in one direction; and Fig. 8 is a similar view showing the relative arrangement of the inner series of port-holes and wheel-blades for running the engine in the opposite direction.

Referring more particularly to the drawings, 1 denotes the outer casing or shell of a turbine, said casing being suitably mounted upon a base 2. The casing 1 is constructed to form a series of compartments 3, any number of which may be provided, three of such compartments being shown in the present instance, these compartments being graduated in size from the inlet to the exhaust ports of the engine. Journaled in suitable bearings 4 at each end of the casing 1 is a centrallydisposed drive-shaft 5, said shaft extending through the casing, as shown.

On the shaft 5 is keyed or otherwise fixedly mounted a series of rotary pistons or turbinewheels 6, one of which is arranged in each of the compartments 3, the circumference of each of said wheels being such that the same will closely it within its respective compartment, so that a steam-tight joint is formed between the periphery of the wheels and the adjacent inner Walls of the compartment in which the same rotates. The turbine-wheels 6 consist of a circular disk or plate 7, having a central concave hub portion 8, around which is formed an inner annular series of obliquely-arranged wings or blades 9, spaced apart to form between themselves steam-passages 10. Around the inner series of blades 9 is formed an outer series of blades 12, said blades 12 being disposed obliquely and at an angle opposite to that of the blades 9. The blades 12 are spaced apart to form between themselves steam-passages 13. The blades 9 and 12 are preferably triangular] y shaped in cross section, thus forming tapering passages between the same, with the wider or flaring end of the blades toward the steam-inlet side of the wheels. The blades 9 and 12 of the inner and outer series of each of said wheels are disposed at opposite angles, thus forming op )ositely-disposed passages between the same, this construction being clearly illustrated in Figs. 7 and 8 of the drawings.

In each of the compartments 3 are arranged partitions or stationary plates 14, through which the shaft 5 passes. The plates "or partitions 14 have a steam-tight connection with the inner walls of the compartments 3 and abut against annular shoulders 15, formed in said inner wall.

Each of the plates 14 is provided with an inner annular series of steam-inlet ports 16, which cooperate with the inner series of blades 9 of the adjacent turbine-wheel. Saidplates 14 are also provided with an outer annular series of steam-inlet ports 17, which cooperate with the outer series of blades 12 of said turbine-wheel. The outer rim of each of the turbine-Wheels beyond the outer series of blades is formed with an annular projection or flange 18, which is adapted to engage and form a steam-tight connection between said wheel and the adjacent port-hole plate. The wheels are also provided between their inner and outer series of blades with an annular groove or recess in which is arranged a ring 19, which is adapted to engage and to have a steam-tight connection with the adjacent porthole plate between the inner and outer series of port-holes in the same. By this arrangement each of the turbine-wheels is adapted to have a steam-tight engagement with its adjacent port-hole plate, which will prevent the leakage of steam between the same.

On the steam-inlet side of each of the porthole plates 14 and between said inner and outer series of port-holes is formed an annular flange 20, which is adapted to engage the adjacent face or outlet side of the turbinewheel between the inner and outer series of blades on the same. The plates 14 are also provided with an inner annular flange 21, which is adapted to engage the adjacent face of the turbine-wheel within the inner series of blades. The flanges 20 and 21 on the porthole plates are adapted to have a steam-tight engagement with the adjacentor outlet side of the turbine-wheel, thus forming annular steam-chambers between the discharge end of the passages formed by the inner and "outer blades of the turbine-wheels and the inlet ends of the port-holes 16 and 17 in the plates 14.

The inner and outer series of port-holes 16 and 17 in the plates 14 are disposed at opposi'te angles in said plates, the inner series of holes 16 being disposed at an opposite angle with respect to the inner series of blades of the adjacent turbine-wheel, while the outer series of port-holes 17 are disposed at an opposite angle with respect to the outer series of blades of said turbine-wheel, so that when the steam is admitted to the inner series of blades through the inner series of ports the engine will be driven in one direction and when the steam is admitted to the outer series of blades through the outer series of portholes the engine will be driven in-the opposite direction, this arrangement of port-holes and blades being clearly illustrated in Figs.

7 and 8 of the drawings. In the rear end of the casing 1 is formedan exhaust-chamber 22, in which is arranged a partition or port-hole plate 23, said plate having formed therein an inner annular series of exhaust port-holes 24, which are adapted to coact with the inner series of blades in the last turbine-wheel to permit the escape of steam discharged therefrom. The partition 23 is also provided with an outer annular series of discharge portholes 25, which are adapted to coact with the outer series of blades of'said turbine-wheel to permit the escape of steam discharged therefrom. Said inner and outer series of discharge-ports 24 and 25 are separated by an annular flange 26, formed on the inner side of the partition or plate 23 and which is adapted to have a steam-tight engagement with the adjacent turbine-wheel between the inner and outer series of blades on the same.

Rotatably mounted upon the drive-shaft 5 and closely engaging the outer side of the partition or plate 23 is a cut-off plate 27, said plate being provided with inner and outer series of port-holes 28 and 29, which when said plate is turned are adapted to be brought into and out of alinement with the inner and outer series of port-holesin said plate 23,thereby permitting the inner series of port-holes 24 to be closed and the outer series to be opened, or vice versa. Any suitable means maybe provided for turning the cut-off plate 27 to bring the port-holes therein into and out of alinement with the port-holes in the plate 23, said mechanism being here shown as preferably consisting in providing the cut-off plate with a radially projecting lug 30, adapted to work through a slot 31, formed in the adjacent side of the casing and covered by means of a segmental box 32, in which is slibably mounted a shifting-rod 33. Said rod passes through packed glands in each end of said box, one end of said rod being pivotally connected to a shifting-lever 34, which is pivotally connected to the side of the casing 1 and is provided with a pawl to coact with a segmental rack 35, whereby said lever may be held in its adjusted positions when actuated to shift the rod 33 to turn the cut-off plate in one direction or the other. The exhaust-compart- 'ment 22 communicates with an exhaust-chambranch pipe 39 is arranged a throttle-valve 41, while in the branch pipe 40 is arranged a throttle-valve 42.

In the main supply-pipe 38 is arranged a controlling-valve 43, the stern of which projects upwardly through the pipe 38 and has IIO connected to its upper end a centrifugal governor 44, which is geared with the drive-shaft 5, whereby when said shaft is rotated at an excessive rate of speed the governor will actuate the stem ofthe valve 43, thus closing said valve to a greater or less degree and limiting the supply of steam to the turbine.

In the first inlet or expansion compartment 3, adjacent to the lirst port-hole plate 14, is

arranged a reversing mechanism, said mechanism being here shown as consisting of a circular cut-off plate or disk 45, rotatably mounted upon the drive-shaft 1 and provided with an inner series of port-holes 46 and an outer series of port-holes 47. Said plate or disk is adapted to be shifted or turned to bring said inner and outer series of port-holes into and out 01 alinement with the inner and outer series of port-holes formed in the adjacent porthole plate 14 to open or close the holes in one or the other of said series, thus admitting steam to one and cutting the same off from the other, whereby owing to the diflerence in the angle or direction of said inner and outer series of ports in the plates 14 the steam will be projected in one direction or the other against the blades of the turbine-wheel, thus determining the direction in which said wheel will be driven. The direction in which the first trubine-wheel is thus turned will determine the direction of movement for all of the tu rbinewheels, as will be understood.

In order that the cut-off plate maybe shifted to bring the inner or outer series of port-holes therein into and out of alinement with the inner and outer series of port-holes in the plate 14, a suitable shifting mechanism is provided. Said mechanism is here shown, and preferably consists in providing the plate 45 with a radially-projecting lug 48, adapted to project into a slot 49, formed inthc casing 1, said slot being covered by a segmental box 50. Slidably mounted in the box and loosely connected to the lug 48 is a shiftingrod 51, said rod projecting through packed glands in the ends of said box and being connected at one end to a shifting-lever 52, pivotally mounted upon the side of the casing 1 and provided with a pawl which is adapted to eoaet with a segmental rack 53, whereby said lever may be held in its adjusted positions when actuated to shift said rod to turn said cut-off plate in one direction or the other to reverse the engine.

On the drive-shaft 5, adjacent to the outer side of the cut-oil plate 45, is fixedly mounted a hub 54, on which is secured two or more radially-projecting -tan-shaped blades, which as the shaft is rotated are adapted to successively cover and uncover certain of the portholes in the cut-off plates-and the port-hole plate 14, thereby admitting steam to said holes suddenly or impulsively. This will impulse, thus aiding the expansive force of steam in the propulsion of said wheel.

On each oi the port-hole plates 14, adjacent to the steam-inlet side of the same, is arranged a vertically-disposed oil-pipe 56, which extends upwardly through the top of the easing 1 and has connected thereto an oil-cup 57, from which oil is adapted to pass through the pipes 56, by which it is discharged upon the drive-shaft 5, thereby lubricating the same at each of said port-hole plates. Other oil-cups 58 are arranged on the bearings 4 to lubricate the shaft at these points.

When it is desired to run the engine at a high speed and a comparatively low power, the throttle-valve 42 and the branch pipe 40 are closed and the throttle-valve 41 in the branch pipe 39 open, thus admitting steam to the first inlet or expansion chamber or compartment 3, where the whole force of the same will be expanded first upon the turbinewheel in this chamber, and from thence it will be exhausted and conducted to the second tur bine-wheel, and so on throughout the series. The turbine-wheels increase in size from the inlet end of the engine toward the discharge end of the same, the larger wheels compensating for the decrease in the power of the steam as itis used and discharged by the successive turbine-wheels.

When it is desired to change the engine from a high speed to a low speed high-power engine, the throttle-valve 41 in thebranch pipe 39 will be closed and the throttle-valve 42 in the branch pipe 40 open, thus cutting the steam off from the first expansion-compartment and its turbine-wheel and admitting the same directly to the second compartment to act. directly upon the second turbine-wheel.

With an engine or turbine construction as herein shown and described a maximum amount of power and speed may be produced, while a minimum amount of floor-space is rc+ quired.

From the foregoing description, taken in connection with the accompanying drawings, the construction and operation of the inven: tion will be readily understood without requiring a more extended explanation.

Various changes in the form, proportion, and the minor details of construction may be resorted to without departingfrom the principle or sacrificing any of the advantages of this invention.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a d rive-shaft journaled on said casing, a turbinewheelfixed on said shaft in each of said com? partments, inner and outer annular series of oppositely-disposed blades arranged on said wheels, aport-hole plate arranged adjacent to each turbine-wheel, said plates having inner and outer annular series of oblique, oppositely-disposed port-holes formed therein to coact with the blades in said wheels, a main steam-supply pipe, branch supply-pipes to form independent connections between said main supply-pipe and said first and second steam expansion compartments, throttlevalves arranged in said branch pipes, and a governor to automatically control the passage of steam through said main supply-pipe, substantially as described.

2. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft journaled on said casing, a turbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of oppositely-disposed blades arranged on said wheels, a port-hole plate arranged adjacent to each turbine-Wheel, said plates having inner and outer annular series of oblique, oppositely-disposed port-holes formed therein to coact with the blades in said Wheels, acut-oif plate having an inner and outer annular series of apertures arranged to coact with the inner and outer series of holes in said port-hole plates to open the holes in one series While closing the holes in the other, and means whereby said cut-0H plate is turned, substantiallyas described.

3. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft jou rnaled on said casing, a tu rhinewheel fixed on said shaft in each of said compartments, inner and outer annular series of oppositely-disposed blades arranged on said wheels, a port-hole plate arranged adjacent to each turbine-wheel, said plates having inner and outer annular series of oblique, oppositely-disposed port-holes formed therein to coact with the blades in said wheels, a cut-01f plate arranged in the first steam inlet and expansion chamber adjacent tothe port-hole plate therein, said cut-off plate having an inner and an outer annular series of apertures so arranged as to open and close either the inner or outer series of holes in said port-hole plates thus changing the direction of steam against the blades of the turbine-wheel, and means whereby the steam is conducted from the inner or outer series of blades of one turbine-wheel to the same series of the next Wheel, substantially as described.

4. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft journaled on said casing, aturbine- Wheel fixed on said shaft in each of said compartments, inner and outer annular series of oppositely-disposed blades arranged on said wheels, a port-hole plate arranged adjacent to each turbine-wheel, said plates having inner and outer annular series of oblique, oppositely-disposed port-holes formed therein to coact withthe blades in said wheels, a cut-off plate arranged in the first steam inlet and expansion chamber adjacent to the port-hole plate therein, said cut-off plate having an inner and an outer annular series of apertures so arranged as to open and close either the inner or outer series of holes in said port-hole plates thus changing the direction of steam against the blades of the turbine-wheel, and means whereby the steam is exhausted from one series of blades on the last turbine-wheel and prevented from entering the other series of the same, substantially as described.

5. In a-steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft journaled on said casing, aturbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of,

oppositely-disposed blades arranged on said wheels, a port-hole plate arranged adjacent toeach turbine-wheel, said plates having inner and outer annular series of oblique, oppositely-disposed port-holes formed therein to coact with the blades in said Wheels, a cut-off plate arranged in the first steam inlet and expansion chamber adjacent .to the port-hole plate therein, said cut-off plate having an inner and an outer annular series of apertures so arranged as to open and close either the inner or outer series of holes in said port-hole plates thus changing the direction of steam against the blades of the turbine-wheel, a stationary exhaust-port plate arranged adjacent to and in rear of the last turbine-wheel, said plate having inner and outer annular series of port-hole plates arranged opposite to the inner and outer series of blades on said turbine-wheel, a revoluble cut-off plate arranged adjacent to said exhaust port-hole plate, said cut-ofi' plate having an inner and outer annular series of openings arranged to open or close either of the inner or outer series of port-holes in said exhaust-plate, and means whereby said cut-off plate is turned, substantially as described.

6. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft journaled on said casing, a turbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of blades arranged on said wheels, said blades being spaced apart and arranged obliquely on the wheels, the blades of one series being disposed opposite to those of the other, a stationary inlet port-hole plate arranged adjacent to and on the steam-inlet side of each of said wheels, said plates having inner and outer series of obliquely-disposed inlet port-holes, said inner series of holes being arranged opposite and at an angle to the inner series of blades, while the outer series of holes are arranged opposite and at an angle to the outer series of blades of said turbine-wheels, an apertured cut-off plate arranged in the first inlet and expansion chamber to open one series of said port-holes and close the other, a shifting lever pivotally mounted on said casing, and means whereby said lever has a steamtight connection with said cut-off plate to actuate the same, substantially as described.

7. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a dri ve-shaft journaled on said casing, a tu rbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of blades arranged on said wheels, said blades being spaced apart and arranged obliquely on the wheels, the blades of one series being disposed opposite to those of the other, a stationary inlet port-hole plate arranged adjacent to and on the steam-inlet side of each of said wheels, said plates having inner and outer series of obliquely-disposed inlet port-holes, said inner series of holes being arranged opposite and atan angle to the inner series of blades, while the outer series of holes are arranged opposite and at an angle to the outer series of blades of said turbine-wheels, an apertured cut-off plate arranged in the first inlet and expansion chamber to open one series of said port-holes and close the other, means whereby said plate is shifted, and means whereby the steam is successively cut off and admitted to certain of said apertures and port-holes in the cut-off and port-hole plate of the first expansion-chamber, substantially as described.

8. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a

. d rive-shaft journaled on said casing, a turbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of blades arranged on said wheels, said blades being spaced apart and arranged obliquely on the wheels, the blades of one series being disposed opposite to those of the other, a stationary inlet port-hole plate arranged adjacent to and on the steam-inlet side of each of said wheels, said plates having inner and outer series of obliquely disposed inlet port-holes, said inner series of holes being arranged opposite and at an angle to the inner series of blades, while the outer series of holes are arranged opposite and at an angle to the outer series of blades of said turbine-Wheels, an apertured eut-ofl' plate arranged in thefirst inlet and expansion chamber to open one series of said port-holes and close the other, a revolving hub secured to the drive-shaft, radially-disposed flat blades secured to said hub and extending across the face of said cut-off plate in the first expansion-chamber whereby the steam is successively out off and admitted to certain of the apertures and port-holes in said cut-off and port-hole plate, substantially as described.

9. In a steam-turbine, the combination with a casing having arranged therein a series of steam inlet and expansion compartments, a drive-shaft jourpaled on said casing, a turbinewheel fixed on said shaft in each of said compartments, inner and outer annular series of triangularly-shaped blades arranged on said wheels, said blades being spaced apart and arranged to form obliquely-disposed tapering passages between themselves, said passages being wider on the steam-inlet side of theturbine-wheels, means whereby steam is introduced to said passages at an angle to the blades, the blades of one of said annular series being disposed at an angle opposite to those of the other, and means whereby steam is admitted to one series and cut off from the other, thus causing the engine to run in one direction or the other, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ELMER K. PURVIS. Witnesses:

GEORGE WV. DUNH'AM, WV. H. NoRRIs; 

